Magnetic resonance for assessment of disease activity and severity in ileocolonic Crohn's disease

OBJECTIVE

Assessment of disease extension and activity is crucial to guide treatment in Crohn's disease. The objective of the current cross-sectional study was to determine the accuracy of MR for this assessment.

DESIGN

50 patients with clinically active (n = 35) or inactive (n = 15) Crohn's disease underwent ileocolonoscopy (reference standard) and MR. T2-weighted and precontrast and postcontrast-enhanced T1-weighted sequences were acquired. Endoscopic activity was evaluated by CDEIS (Crohn's Disease Endoscopic Index of Severity); in addition endoscopic lesions were classified as absent, mild (inflammation without ulcers) or severe (presence of ulceration).

RESULTS

The comparison of intestinal segments with absent, mild and severe inflammation demonstrated a progressive and significant (p<0.001) increase in the following MR parameters: wall thickness, postcontrast wall signal intensity, relative contrast enhancement, presence of oedema, ulcers, pseudopolyps and lymph node enlargement. Independent predictors for CDEIS in a segment were wall thickness (p = 0.007), relative contrast enhancement (p = 0.01), presence of oedema (p = 0.02) and presence of ulcers at MR (p = 0.003). There was a significant correlation (r = 0.82, p<0.001) between the CDEIS of the segment and the MR index calculated according to the logistic regression analysis coefficients. The MR index had a high accuracy for the detection of disease activity (area under the receiver operating characteristic (ROC) curve 0.891, sensitivity 0.81, specificity 0.89) and for the detection of ulcerative lesions (area under the ROC curve 0.978, sensitivity 0.95, specificity 0.91) in the colon and terminal ileum.

CONCLUSION

The accuracy of MR for detecting disease activity and assessing severity brings about the possibility of using MR as an alternative to endoscopy in the evaluation of ileocolonic Crohn's disease.

Neurocysticercosis: association between seizures, serology, and brain CT in rural Peru

BACKGROUND

Neurocysticercosis (NCC) is the commonest helminthic CNS infection and the main cause of adult-onset seizures in developing countries, also frequent in industrialized countries because of immigration from endemic zones. Although NCC is commonly seen in individuals with seizures in endemic areas, its role as a cause of epilepsy has been questioned on the basis of the poor methodology of published studies.

OBJECTIVE

To determine, in a cysticercosis-endemic area of the northern Peruvian coast, the frequency of 1) epileptic seizures, 2) serum antibodies to Taenia solium, 3) NCC-compatible findings on brain CT, and 4) the associations between these variables.

METHODS

A community-wide screening survey for possible seizure cases was performed using a validated questionnaire. Positive respondents were later examined in the field by neurologists. Seizure cases were categorized as single seizure, active epilepsy, or inactive epilepsy. Serology was performed for all consenting individuals using immunoblot. Noncontrast brain CT scans were performed in all individuals with seizures and two groups of control subjects without seizures (seropositive and seronegative).

RESULTS

The screening survey was applied to 903 permanent residents. Most positive respondents (114/137 [83.2%]) were examined by neurologists. The overall prevalence of epilepsy was 32.1 per 1,000 and that of active epilepsy was 16.6 per 1,000. Seroprevalence was 24.2% (200/825). Seroprevalence was associated with seizures (odds ratio 2.14; p = 0.026). Brain CT abnormalities compatible with NCC were more frequent in individuals with seizures and in those seropositive.

CONCLUSION

In this hyperendemic area, an important proportion of seizure cases are associated with neurocysticercosis as demonstrated by serology or brain CT.

Release of volatiles from a possible cryovolcano from near-infrared imaging of Titan

Titan is the only satellite in our Solar System with a dense atmosphere. The surface pressure is 1.5 bar (ref. 1) and, similar to the Earth, N2 is the main component of the atmosphere. Methane is the second most important component, but it is photodissociated on a timescale of 10(7) years (ref. 3). This short timescale has led to the suggestion that Titan may possess a surface or subsurface reservoir of hydrocarbons to replenish the atmosphere. Here we report near-infrared images of Titan obtained on 26 October 2004 by the Cassini spacecraft. The images show that a widespread methane ocean does not exist; subtle albedo variations instead suggest topographical variations, as would be expected for a more solid (perhaps icy) surface. We also find a circular structure approximately 30 km in diameter that does not resemble any features seen on other icy satellites. We propose that the structure is a dome formed by upwelling icy plumes that release methane into Titan's atmosphere.

Randomized, double-blind, placebo-controlled dose-ranging study of tirofiban (MK-383) platelet IIb/IIIa blockade in high risk patients undergoing coronary angioplasty

OBJECTIVES

The objectives of this double-blind, placebo-controlled, randomized dose-ranging study were 1) to examine the safety and tolerability of tirofiban (MK-383), a new nonpeptide platelet IIb/IIIa receptor antagonist, on a background of intravenous heparin and aspirin therapy; 2) to study the pharmacodynamics and pharmacokinetics of tirofiban; and 3) to evaluate the incidence of adverse cardiac outcomes (urgent repeat revascularization, myocardial infarction and death) with tirofiban versus placebo in a high risk subset of patients undergoing coronary angioplasty.

BACKGROUND

Abrupt vessel closure complicates 4% to 8% of angioplasty procedures. Recent data have suggested that agents that antagonize the platelet glycoprotein IIb/IIIa receptor may reduce the incidence of adverse ischemic outcomes after coronary angioplasty.

METHODS

Seventy-three patients received tirofiban in three sequential dose panels and 20 patients received placebo. Patients within each panel were randomized to receive either tirofiban or placebo in a 3:1 randomization design. Bolus doses of 5, 10 and 10 microg/kg and continuous infusion (16 to 24 h) doses of 0.05, 0.10 and 0.15 microg/kg per min were administered in panels I, II and III, respectively. Patients received concomitant heparin and aspirin for the angioplasty procedure. Data on patients receiving placebo (heparin and aspirin only) were pooled across panels for comparisons. The pharmacodynamic effect of tirofiban on ex vivo platelet aggregation to 5 micromol/liter adenosine diphosphate (ADP) and bleeding times were measured. Clinical outcomes were assessed in all patients, but the power to detect clinically meaningful differences (a one-third reduction in clinical events) between groups was limited (5%).

RESULTS

Tirofiban was associated with a dose-dependent inhibition of ex vivo ADP-mediated platelet aggregation that was sustained during intravenous infusion and resolved rapidly after drug cessation. Adverse bleeding events, largely related to vascular access site hemorrhage, were slightly increased at the highest dose. Adverse clinical outcomes were infrequent in all patients and were not different among the small number of patients within each group.

CONCLUSIONS

This study establishes a rational and generally well tolerated dosing regimen for administration of tirofiban as adjunctive therapy in high risk angioplasty patients. The impact of tirofiban on adverse clinical outcomes after angioplasty awaits definition by a larger clinical trial.

Oxidation of Orange G by persulfate activated by Fe(II), Fe(III) and zero valent iron (ZVI)

Persulfate (PS) was employed in the oxidation of Orange G (OG), an azo dye commonly found in textile wastewaters. Activation of PS was conducted with iron to generate sulfate free radicals (SO4(-)) with high redox potential capable to oxidize most of the organics in water. Identification of oxidation intermediates was carried out by analyzing at different times organic by-products generated from treatment of a concentrate dye solution (11.6 mM) with 153 mM of PS and 20 mM of Fe(II) at 20 °C. Intermediate reaction products (mainly phenol (PH) and benzoquinone (BQ), and in less extent aniline, phenolic compounds and naphthalene type compounds with quinone groups) were identified by GC/MS and HPLC, and an oxidation pathway was proposed for the oxidation of OG with iron activated PS. The effect of iron valence (0, II and III) in the oxidation of an aqueous solution of OG (containing 0.1 mM) was studied in a 0.5 L batch reactor at 20 °C. Initial activator and PS concentrations employed were both 1 mM. Complete pollutant removal was achieved within the first 30 min when iron II or III were employed as activators. Quinone intermediates generated during pollutant oxidation may act as electron shuttles, allowing the reduction of Fe(III) into Fe(II) in the redox cycling of iron. Therefore, activation of PS by Fe(III) allowed complete OG removal. When zero valent iron (ZVI) was employed (particle diameter size 0.74 mm) the limiting step in SO4(-) generation was the surface reaction between ZVI and the oxidant yielding a lower oxidation rate of the dye. An increase in the oxidant dosage (0.2 mM OG, 2 mM Fe(III) and 6 mM PS) allowed complete pollutant and ecotoxicity removal, as well as mineralization close to 75%.

Latent autoimmune hepatitis triggered during interferon therapy in patients with chronic hepatitis C

BACKGROUND/AIMS

Interferon can induce autoantibodies and autoimmune reactions. This study reviewed the clinical, serological, and HLA phenotypical features of patients who developed autoimmune hepatitis during interferon therapy for chronic hepatitis C, analyzing their response to immunosuppressive treatment.

METHODS

The diagnosis of chronic hepatitis C was based on positivity for viral RNA and a liver biopsy specimen obtained before interferon treatment. Sera were tested for autoantibodies by indirect immunofluorescence assay. HLA typing was performed by applying a standard microlymphocytotoxicity method.

RESULTS

Of 144 patients with chronic hepatitis C treated with interferon, 7 women deteriorated during treatment; serum transaminase, gamma-globulin, and immunoglobulin G levels increased; and serum autoantibodies became positive. Interferon was interrupted, a diagnosis of autoimmune hepatitis was established, and immunosuppressive therapy was initiated. All patients responded to this treatment. The 7 patients had similar HLA typing to those with autoimmune hepatitis, with DR4 in 2 patients (67%) with type 2 autoimmune hepatitis, and with DR3 and DR52 in 2 (50%) and 4 (100%) patients, respectively, with type 1 autoimmune hepatitis; additionally, 5 patients (71%) had DQ2, and 4 (57%) had both DR52 and DQ2.

CONCLUSIONS

In female patients with chronic hepatitis C, a genetic susceptibility to autoimmune hepatitis may exist, possibly triggered by immunostimulating effects during interferon therapy. Immunosuppressive treatment has been well tolerated and seems to be effective.

Expression profile of genes from 12p in testicular germ cell tumors of adolescents and adults associated with i(12p) and amplification at 12p11.2-p12.1

Gain of 12p material is invariably associated with testicular germ cell tumors (TGCTs) of adolescents and adults, most usually as an isochromosome 12p. We analyzed TGCTs with i(12p) using a global approach to expression profiling targeting chromosomes (comparative expressed sequence hybridization, CESH). This indicated overexpression of genes from 12p11.2-p12.1 relative to testis tissue and fibroblasts. The nonseminoma subtype showed higher levels of expression than seminomas. Notably, 12p11.2-p12.1 is amplified in about 10% of TGCTs and CESH analysis of such amplicon cases showed high levels of overexpression from this region. Microarray analysis, including cDNA clones representing most UniGene clusters from 12p11.2-p12.1, was applied to DNA and RNA from 5 TGCTs with amplification of 12p11.2-p12.1 and seven TGCTs with gain of the entire short arm of chromosome 12. Expression profiles were consistent with the CESH data and overexpression of EST595078, MRPS35 and LDHB at 12p11.2-p12.1 was detected in most TGCTs. High-level overexpression of BCAT1 was specific to nonseminomas and overexpression of genes such as CMAS, EKI1, KRAS2, SURB7 and various ESTs correlated with their amplification. Genes such as CCND2, GLU3, LRP6 and HPH1 at 12p13 were also overexpressed. The overexpressed sequences identified, particularly those in the region amplified, represent candidate genes for involvement in TGCT development.

Incidence, cost, and outcomes of bleeding and chemotherapy dose modification among solid tumor patients with chemotherapy-induced thrombocytopenia

PURPOSE

To describe the incidence and outcomes of bleeding and chemotherapy dose modifications associated with chemotherapy-induced thrombocytopenia (platelets < 50,000/microL).

PATIENTS AND METHODS

Six hundred nine patients with solid tumors or lymphoma were followed-up during 1,262 chemotherapy cycles complicated by thrombocytopenia for development of bleeding, delay or dose reduction of the subsequent cycle, survival, and resource utilization. The association between survival and bleeding or dose modification was examined using the Cox proportional hazards model. Predisposing factors were identified by logistic regression.

RESULTS

Bleeding occurred during 9% of cycles among patients with previous bleeding episodes (P <.0001), baseline platelets less than 75,000/microL (P <.0001), bone marrow metastases (P =.001), poor performance status (P =.03), and cisplatin, carboplatin, carmustine or lomustine administration (P =.0002). Major bleeding episodes resulted in shorter survival and higher resource utilization (P <.0001). Chemotherapy delays occurred during 6% of cycles among patients with more than five previous cycles (P =.003), radiotherapy (P =.03), and disseminated disease (P =.04). They experienced similar clinical outcomes but used significantly more resources. Dose reductions occurred during 15% of cycles but were not associated with poor clinical outcomes or excess resource utilization. Significantly shorter survival and higher resource utilization were observed among the 20% of patients who failed to achieve an adequate response to platelet transfusion.

CONCLUSION

The incidence of bleeding is low among solid tumor patients overall but exceeds 20% in some subgroups. These subgroups are easily identifiable using routinely available clinical information. A clinical prediction rule is being developed. Poor response to platelet transfusion is a clinically and financially significant downstream effect of thrombocytopenia and warrants further investigation.

Clostridial bacteremia in cancer patients. A 12-year experience

Over 12 years, 136 episodes of bacteremia caused by clostridial species were documented. Eighty-three were monomicrobial, and 53 were polymicrobial. Gastrointestinal, genitourinary carcinomas, and acute leukemia were the most common underlying malignancies. Septic shock occurred in 29% of monomicrobial bacteremias and 45% of polymicrobial bacteremias and was associated with a high mortality rate. Acute hemolysis, gas gangrene, and diffuse spreading cellulitis occurred infrequently but were associated with a 100% fatality rate. Many infections caused by Clostridium perfringens and C. septicum were associated with abdominal disease. The most commonly isolated organism was C. perfringens, followed by C. septicum and C. sporogenes. Overall survival was 58%, but it was 66% for monomicrobial episodes and 45% for polymicrobial infections. All of the patients with bacteremia due to an aerobic gram-negative bacillus in addition to the clostridial species died of their infection. The most effective antibiotics were clindamycin, penicillin, metronidazole, and moxalactam. Surgical drainage of abscesses was an important component of therapy.

Short report: transient antibody response in Taenia solium infection in field conditions-a major contributor to high seroprevalence

The discordance between extremely high seroprevalence of Taenia solium antibodies in disease-endemic populations, relatively few symptomatic cases of neurocysticercosis, and high background levels of putatively inactive brain lesions (mainly calcifications) in seronegative controls have confused researchers, clinicians, and epidemiologists in the last decade. We reviewed longitudinal serologic data from general population serosurveys in 3 different disease-endemic areas of Peru and Colombia and found that approximately 40% of seropositive people were seronegative when resampled after 1 year (3 surveys) or after 3 years (1 survey). Transient antibodies may have significant implications for the epidemiology of and immunity to this disease.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Pulmonary infections mimicking cancer: a retrospective, three-year review

Pulmonary infections can mimic or occasionally co-exist with pulmonary neoplasms. In order to determine the frequency and nature of these infections, we conducted a retrospective analysis, covering a 3-year period, of patients who were referred to our center with presumed lung cancer but turned out to have pulmonary infection instead. The overwhelming majority of patients (93.3%) referred to "rule out" lung cancer were documented as having a neoplastic process, and only 1.3% had an infection. Fungal infections (histoplasmosis, cryptococcosis, coccidiomycosis) accounted for 46%, mycobacteria for 27%, bacteria for 22%, and parasitic lesions (dirofilariasis) for 5% of these infections. The most common clinical manifestations were cough and chest pain, and the most common radiographic finding was a solitary pulmonary nodule. There were no specific clinical or radiographic features predictive of either infection or neoplastic disease. All patients responded to specific anti-infective therapy with or without surgical excision. Our data indicate that pulmonary infections mimic neoplasms very infrequently. However, establishing a specific diagnosis is critical, since the management and outcome of these two processes are entirely different.

Infusion phlebitis in patients with acute pneumonia: a prospective study

STUDY OBJECTIVES

To prospectively assess the relative risk for phlebitis in a series of consecutive patients with pneumonia and to identify risk factors that predict an increased risk for phlebitis.

SETTING

Internal medicine department of a tertiary teaching hospital.

PATIENTS

Seven hundred sixty-six consecutive patients with acute pneumonia receiving IV therapy.

INTERVENTIONS

Only the first catheter was taken into account. There were 308 short lines (a 51-mm, 18-gauge Teflon catheter); 307 midsized lines (a 28-cm, 16-gauge polyvinyl chloride catheter); and 151 long lines (71-cm, 14-gauge plain polyurethane catheter). Eighteen variables were prospectively evaluated in an open, nonrandomized study for their contribution to the occurrence of phlebitis.

RESULTS

The overall phlebitis rate was 39%. Phlebitis developed in 53% of patients with short lines, in 41% of patients with midsized lines, and in 10% of patients with long lines, and these catheters remained in place an average (+/- SD) of 3.0+/-2.4 days, 4.6+/-3.4 days, and 7.8+/-6.6 days, respectively. The variables that influenced the development of phlebitis, as determined by multivariate analysis, were the following: type of catheter; blood hemoglobin levels; and IV therapy with either corticosteroids or erythromycin.

CONCLUSIONS

According to our data, when the use of a catheter is expected to be required for < or = 36 h, a short line can be used. If a longer duration is expected, a longer line is warranted. Ours is the first study in which the relationship between blood hemoglobin levels and phlebitis has been reported. Because the use of intravascular devices is increasingly common, a more complete knowledge of the factors that influence their acceptance has become essential.

Neurocysticercosis: unraveling the nature of the single cysticercal granuloma

A single enhancing lesion in the brain parenchyma, also called an inflammatory granuloma, is a frequent neurologic diagnosis. One of the commonest causes of this lesion is human neurocysticercosis, the infection by the larvae of the pork tapeworm, Taenia solium. Following the demonstration that viable cysticercosis cysts survive in good conditions for several years in the human brain, single cysticercal granulomas have been consistently interpreted as representing late degeneration of a long-established parasite. On the basis of epidemiologic, clinical, and laboratory evidence detailed in this article, we hypothesize that in most cases these inflammatory lesions correspond to parasites that die in the early steps of infection, likely as the natural result of the host immunity overcoming mild infections.

Abatement of chlorinated compounds in groundwater contaminated by HCH wastes using ISCO with alkali activated persulfate

In this work, in situ chemical oxidation (ISCO) with alkali activated persulfate has been tested for the elimination of HCH isomers and other chlorinated compounds in groundwater from Sabiñanigo (Sardas landfill), which was contaminated by solid and liquid wastes illegally dumped in the area by a company producing lindane. Due to the site lithology and the type of pollutants found in groundwater (HCHs and chlorobenzenes) alkali (NaOH) activated persulfate (PS) was selected as oxidant. The influence of variables such as PS concentration (42-200mM) and NaOH:PS molar ratio (2:1 to 4:1) on chlorinated compound abatement has been studied and a kinetic model to predict the composition of all chlorinated organic compounds (COCs) in the aqueous phase with time was obtained. It was found that a fast initial hydrodechlorination reaction took place in which HCH isomers reacted to trichlorobenzenes (mainly 1,2,4 TCB) at pH≥12. Mono-, di-, tri and tetrachlorobenzenes remaining were oxidized without producing aromatic intermediates. At the condition tested a first order kinetic model for COCs and PS concentration was obtained. Zero order alkali concentration was obtained while pH was being kept at 12 for the whole reaction time.

When the earth trembles in the Americas: the experience of Haiti and Chile 2010

The response of the nephrological community to the Haiti and Chile earthquakes which occurred in the first months of 2010 is described. In Haiti, renal support was organized by the Renal Disaster Relief Task Force (RDRTF) of the International Society of Nephrology (ISN) in close collaboration with Médecins Sans Frontières (MSF), and covered both patients with acute kidney injury (AKI) and patients with chronic kidney disease (CKD). The majority of AKI patients (19/27) suffered from crush syndrome and recovered their kidney function. The remaining 8 patients with AKI showed acute-to-chronic renal failure with very low recovery rates. The intervention of the RDRTF-ISN involved 25 volunteers of 9 nationalities, lasted exactly 2 months, and was characterized by major organizational difficulties and problems to create awareness among other rescue teams regarding the availability of dialysis possibilities. Part of the Haitian patients with AKI reached the Dominican Republic (DR) and received their therapy there. The nephrological community in the DR was able to cope with this extra patient load. In both Haiti and the DR, dialysis treatment was able to be prevented in at least 40 patients by screening and adequate fluid administration. Since laboratory facilities were destroyed in Port-au-Prince and were thus lacking during the first weeks of the intervention, the use from the very beginning on of a point-of-care device (i-STAT®) was very efficient for the detection of aberrant kidney function and electrolyte parameters. In Chile, nephrological problems were essentially related to difficulties delivering dialysis treatment to CKD patients, due to the damage to several units. This necessitated the reallocation of patients and the adaptation of their schedules. The problems could be handled by the local nephrologists. These observations illustrate that local and international preparedness might be life-saving if renal problems occur in earthquake circumstances.

Effects of oral rabeprazole on oesophageal and gastric pH in patients with gastro-oesophageal reflux disease

BACKGROUND

This study examined the dose-response effects of the new proton-pump inhibitor rabeprazole on oesophageal and gastric pH in patients with gastro-oesophageal reflux disease.

METHODS

This study had a single-centre, double-blind, randomized, two-way crossover design. Twenty patients were treated for two 7-day periods separated by a 7-10-day washout period. Patients were randomly assigned to receive either 20 mg of rabeprazole once daily during the first treatment period and 40 mg once daily during the second treatment period, or 40 mg during the first treatment period and 20 mg during the second treatment period. The primary efficacy variable was oesophageal acid exposure determined by 24-hour ambulatory pH monitoring. Acid-reflux time was defined as the percentage of time over 24 h that oesophageal pH was < 4. A dosage was considered effective if reflux time was reduced to < 6%, a number which has been our internal laboratory reference.

RESULTS

Both rabeprazole 20 mg and 40 mg, given once daily, normalized reflux time, with decreases of 79% and 92% in acid exposure by day 7. Both dosages also decreased the mean total number of reflux episodes and the number of episodes lasting > 5 min, with no significant differences between dosages for any reflux parameter. Mean gastric pH increased with 20 mg from 1.86 at baseline to 3.71 on day 1 and 4.17 on day 7. Rabeprazole 40 mg once daily increased gastric pH from 2.01 to 4.37 on day 1, and to 4.65 on day 7. Safety analyses revealed no significant acute side-effects for either dosage.

CONCLUSIONS

Pathological oesophageal acid exposure was normalized with both 20 mg and 40 mg dosages of rabeprazole, and the effects of these two doses did not differ. Rabeprazole was well-tolerated in this short-term study.